There is no connection between illuminated, nocturnal calls of nature and cancer, despite what certain newspapers are claiming...

Professor Kyriacou and Dr Ben-Shlomo suggest in their conclusion, that the chronic exposure of shift workers to extended light schedules during what should be their ‘night’, may also misregulate these cell cycle genes, and could conceivably contribute to the elevated levels of tumours seen in this population.

But nowhere in their paper, which is published in the journal Cancer Genetics and Cytogenetics, do they mention trips to the toilet or anything even vaguely similar.